It's day #1.
The number of applications in the App Store is only going to grow from here out, and as the software developers become more familiar with how their apps perform in the real world, the coding is only going to get better. So hopefully you'll see bug fixes for your eBook problems soon and be able to see how easily the upgrade process works.
I wouldn't judge the whole iPhone 2.0 upgrade just on my experiences from today.
thats what i was going to say,
but yeah its barely day one the apps are giong to grow insanely, like when they first launch itunes do you think they had millions of songs and that was it? no they started off with a few then it grew to what it is today